The present invention relates to a device for influencing the driving dynamics of a vehicle with an electronic brake system comprising a brake actuator by which a brake torque is adjustable on at least one wheel brake of the vehicle, and the brake torque can be determined in a torque distributing device according to a yaw torque requirement, and comprising a first control unit which can be activated in the presence of a critical driving condition, the said first control unit being used to determine a first yaw torque requirement due to driving dynamics control.
The invention relates further to a method for influencing the driving dynamics of a vehicle.
Driving dynamics control systems for vehicles are known in the art e.g. by the name ESP (Electronic Stability Program), which stabilize the vehicle in critical driving situations by brake interventions on each individual wheel. The control systems are usually integrated into a brake controlling apparatus of the vehicle and include a control unit and a torque distributing unit. A yaw torque requirement is determined in the control unit depending on a deviation of an actual yaw rate from a nominal yaw rate of the vehicle and depending on the current sideslip angle of the vehicle. Based on this requirement, the torque distribution unit determines the brake torques or brake pressures on each individual wheel, which are set in the wheel brakes by means of a brake actuator.
Besides, driving dynamics control systems for influencing the driving behavior in subcritical driving situations have become known. It is an objective of these controls to improve the vehicle behavior following an intervention, i.e. to reach an improved and direct reaction of the vehicle to the driving commands of the driver and, thus, a more agile driving behavior.
In addition to the brake actuator, additional actuators can be driven to this end in order to influence the driving behavior of the vehicle. In this respect, a so-called overriding steering system can be concerned, which is used to perform steering interventions at the front wheels, a rear-axle steering system, which allows steering interventions at steerable rear wheels of the vehicle, controllable chassis elements such as adjustable dampers or adjustable stabilizers, or controllable elements of the drive train, such as electronically controllable differential locks. In contrast to brake interventions, the interventions of additional actuators of this type are advantageous in that the driver does not notice them as disturbing because the vehicle does not decelerate.
In frequent cases, the control systems for driving the additional actuators relate to systems, which are separated from the ESP system. The problem encountered in this respect is that a superposition of control interventions may occur in critical driving situations, which causes amplification or reduction of the intended effect.
An object of the invention is to render cross-linking of control systems for driving dynamics control possible in critical and subcritical driving situations and to coordinate especially a superposition of control interventions of both systems.